Air directing apparatus



y 1962 J. SCARR, JR 3,033,278

AIR DIRECTING APPARATUS Filed Dec. 22, 1958 INVENTOR.

United States Patent Cfifice 3,033,278 Patented May 8, 1962 3,033,278 AIR DIRECTIN G APPARATUS John Scan, Jr., Penn Hills Township, Allegheny County,

Pa., assignor to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware Filed Dec. 22, 1958, Ser. No. 782,061 5 Claims. (Cl. 15876) The present invention relates to combustion apparatus of the type wherein a gun-type burner nozzle is disposed in an air blast tube, and more particularly pertains to new and useful improvements in air turbulators associated with such combustion apparatus.

In general, the invention is concerned with the provision of air turbulator means conductive to reducing the smoke number while increasing the carbon dioxide content of the combustion products. It has been found that such results can be obtained upon positioning a cup-shaped turbulator or distributor concentrically within the blast tube in spaced relation thereto, such cupshaped distributor opening toward the nozzle and having a central opening in the bottom thereof. Furthermore, it has been found that even more favorable results of the character specified above can be obtained if the bottom of the cup-shaped distributor is provided with a plurality of circumferentially spaced, radial slots about the periphery of the opening, particularly when the slots are inclined to the bottom of the distributor. The performance of the cup-shaped distributor is further enhanced by the provision of helical vanes in the space intermediate the distributor and the blast tube.

Inasmuch as extant turbulators include a blast tube or blast tube extension provided with internal helical vanes that terminate radially at an equal distance from the axis of the tube or extension for a substantial portion of their axial extent, and inasmuch as the efficiency of the cup-shaped distributor is affected by the axial spacing of the distributor relative to the nozzle, the invention is also concerned with the provision of a cup-shaped distributor according to the invention that can be furnished as an adjunct to extant air turbulators for improving combustion efliciency and for cooperating therewith in such a manner that the vanes of the extant turbulators retain the distributor in concentric relation with respect to the blast tube.

The invention will be best appreciated upon reference to the accompanying drawings illustrative of a preferred embodiment thereof, wherein FIGURE 1 is a transverse sectional view of combustion apparatus according to the invention and is taken upon the plane of the section line I--I of FIGURE 2, and wherein FIGURE 2 is a central sectional view taken upon the plane of the section line II-II in FIGURE 1 with a portion of the distributor being broken away and with the nozzle, its supply conduit, and the distributor set screw being shown in elevation.

The numeral designates an air blast tube in which is concentrically disposed a conventional high-pressure, gun-type burner nozzle 12 and the fuel supply conduit .14 for the nozzle 12.

A primary air turbulator designated generally at 16 {is attached to the discharge end of the blast tube 10, such :turbulator 16 being comprised of a tubular member that includes a reduced cylindrical section 18 that is fitted 'within the discharge end of the blast tube 10 and a terminal section 20 that is inturned as shown, and a plurality of helical vanes 22 fixed to such tubular member extending substantially the entire axial extent of the sections 18 and 20 thereof. The turbulator 16 in effect constitutes an extension of the blast .tube 10 and is secured thereto simply by being press fitted therein, but alternatively can be welded on or, if desired, the turbulator 16 can be detachably secured to the blast tube 10 by one or more set screws in the tube 10 engaging the cylindrical section 18 of the turbulator.

As clearly shown in FIGURE 2, the interior of the terminal section 20 of the turbulator 16 defines a curved and smoothly convergent surface that terminates in a circular discharge opening 24. The vanes 22 terminate with respect to their radial extent at a distance from the central axis of the turbulator 16 equal to the radius of the opening 24, so that the vanes 22 can be considered as defining a hypothetical cylindrical surface that coincides with the periphery of the opening 24.

The numeral 26 designates generally a further turbulator or distributor. The distributor is cup-shaped and comprised of a bottom 28 and sides 30, the same being arranged to open toward the nozzle 12. The external surface of the sides 30 is cylindrical and of approximately the same diameter as the hypothetical cylindrical surface mentioned in the preceding paragraph so that the distributor 26 is retained in concentric relation with the blast tube 10 by the vanes 22, but with suflicient looseness of fit that the distributor can be moved axially. The distributor is releasably secured in axially adjusted position by means of a set screw 32 threaded through the distributor 26 to engage the interior of the turbulator 16, as shown.

The bottom of the distributor 26 is provided with a central opening 34 of substantiallyless diameter than the distributor 26, and in the preferred structure illustrated, a plurality of circumferentially spaced, radially extending slots 36 are provided in the bottom 28. The slots 36 can, if desired, be more or less in number than as illustrated. In addition, it is preferred that the slots 36 be of lesser width than the thickness of the bottom 28 and inclined to the plane on which the bottom 28 lies as best shown in FIGURE 2.

The operation of the apparatus shown in the drawings is readily apparent. A portion of the air passing through the blast tube 10 passes through the annular space between the distributor 26 and the cylindrical section 18 of the turbulator 16 and is given a swirling motion by the vanes 22, and is directed inwardly toward the central axis as it is discharged through the opening 24. Another portion of the air passes into the distributor 26 and out the opening 34 thereof closely adjacent the central axis and thence out the opening 24. The performance of the apparatus is affected by the axial position in which the distributor 26 is adjusted, this being in part due to the valving action obtained upon the distributor 26 being positioned near the opening 24 with respect to air by-passing the exterior of the distributor 26.

Tests made with respect to apparatus according to the invention using a nozzle rated at about one gallon per hour have shown that for a smoke number of one, as determined by a standard filter test method, using the turbulator 16 without the distributor 26, the combustion products contained only 9.25 percent carbon dioxide, but that under otherwise identical conditions except for the additional use of the distributor 26, a carbon dioxide content of 11 percent was obtained. This amounts to a very significant improvement of about 19 percent in carbon dioxide content, and indicates a greatly improved combustion efficiency realized upon the use of the distributor 26.

One of the chief advantages of the invention is that the distributor 26 can be conveniently attached to extant conventional turbulators such as that shown at 16 to improve combustion efiiciency, it being understood that it is not essential that the fit of the distributor 26 in the vanes 22 be perfect. In fact, the distributor 26 can be employed with only a simple blast tube, that is without a turbulator 16, though it is preferred that the blast tube 3 include an inturned extremity such as that provided in effect by the section of the turbulator 16. When the vanes 22 are omitted, the distributor 26 should be provided with sufficient additional set screws 32 to secure the distributor 26 in axially adjusted and concentric relation to the blast tube.

The illustrated preferred embodiment of the invention is susceptible to numerous variations without departing from the spirit of the invention. The concept of the invention encompasses such changes as forming the turbulator 16 and the distributor 26 as an integral body, and where the bottom 28 is made of relatively thin metal and the number of slots 36 is large, the portions of the bottom 28 intermediate the slots 36 can be bent or twisted about radial axes in lieu of or in addition to the slots 36 being inclined. Accordingly, the actual scope of the invention should be ascertained on reference to the appended claims.

I claim:

1. Combustion apparatus comprising a blast tube having a discharge end, a nozzle concentrically positioned in the blast tube and directed toward the discharge end of the latter, a cup-shaped distributor having sides and a bottom, said distributor being concentrically disposed within the blast tube and spaced therefrom and opening away from the discharge end of the blast tube, the bottom of said distributor being intermediate the nozzle and the discharge end of the blast tube and having a central opening therethrough of substantially less diameter than the distributor, and said bottom of the distributor being provided with a plurality of circumferentially spaced, radially extending slots about the periphery of the opening therethrough, said slots being of a width less than the thickness of the bottom of the distributor and being inclined to the plane on which the bottom of the distributor lies.

2. Combustion apparatus comprising a blast tube having a discharge end, a nozzle concentrically positioned in the blast tube and directed toward the discharge end of the latter, a cup-shaped distributor having sides of cylindrical external configuration and a bottom, said blast tube having secured thereto adjacent its discharge end a plurality of circumferentially spaced, radially inward extending vanes, said distributor being concentrically disposed Within the blast tube and opening away from the discharge end of the blast tube with the bottom of the distributor being intermediate the nozzle and the discharge end of the blast tube, said vanes radially terminating in sliding engagement with the exterior of the sides of the distributor to retain the latter in concentric relation with the blast tube, with the distributor being axially movable, means for securing the distributor in axially adjusted position, and the bottom of the distributor having a central opening of substantially less diameter than the distributor.

3. Combustion apparatus comprising a blast tube having a discharge end, a nozzle concentrically positioned in the blast tube and directed toward the discharge end of the latter, a cup-shaped distributor having sides of cylindrical external configuration and a bottom, said blast tube having secured thereto adjacent its discharge end a plurality of circumferentially spaced, radially inward extending helical vanes, said distributor being concentrically disposed within the blast tube and opening away from the discharge end of the blast tube with the bottom of the distributor being intermediate the nozzle and the discharge end of the blast tube, said vanes radially terminating in sliding engagement with the exterior of the sides of the distributor to retain the latter in concentric relation with the blast tube, with the distributor being axially movable, means for securing the distributor in axially adjusted position, said bottom of the distributor having a central opening, and said bottom being provided with a plurality of circumferentially spaced, radially extending slots about the periphery of the opening therethrough, said slots being of a width less than the thickness of the bottom of the distributor and being inclined to the plane on which the bottom of the distributor lies.

4. Combustion apparatus comprising a blast tube having a discharge end, a nozzle concentrically positioned in the blast tube and directed toward the discharge end of the latter, a cup-shapeddistributor having sides of cylindrical external configuration and a bottom, said blast tube having secured thereto adjacent its discharge end a plurality of circumferentially spaced, radially inward extending vanes, said distributor being concentrically disposed within the blast tube and opening away from the discharge end of the blast tube with the bottom of the distributor being intermediate the nozzle and the discharge end of the blast tube, said vanes radially terminating in sliding engagement with the exterior of the sides of the distributor to retain the latter in concentric relation with the blast tube, with the distributor being axially movable, said blast tube being inturned adjacent its discharge end, means for securing the distributor in axially adjusted position, and the bottom of the distributor having a central opening of substantially less diameter than the distributor.

5. An air blast tube attachment for use in combustion equipment comprising a blast tube extension comprised of a tubular member inturned adjacent one end thereof to define a reduced opening having a center on the axis of the extension and lying on a transverse plane at the end of said extension, a cup-shaped distributor concentrically disposed in the extension, said distributor having sides of external cylindrical configuration of a diameter approximately that of the discharge opening and a bottom, said cup-shaped distributor being entirely on one side of the transverse plane of said discharge opening, the bottom of said cup-shaped distributor being relatively closer to said plane and the top of said cup-shaped distributor being relatively more removed from said plane so that said cup-shaped distributor opens away from said discharge opening, radial vanes fixed to the interior of the extension that cooperate with the external cylindrical configuration of the sides of the distributor to confine the latter to said concentric relation with sufiicient looseness that the distributor is axially moveable in the extension, means for securing the distributor in axially adjusted position, and said bottom of the distributor having a central opening substantially smaller than said discharge opening.

References Cited in the file of this patent UNITED STATES PATENTS 1,976,097 Sharp Oct. 9, 1934 2,041,348 Johnson May 19, 1936 2,156,121 Macrae Apr. 25, 1939 2,219,696 Mueller et al. Oct. 29, 1940 2,569,754 Gressley Oct. 2, 1951 2,616,493 Winters Nov. 4, 1952 2,815,805 Czarnecki Dec. 10, 1957 

